Alpha Particles

- Highly charged, heavy particles
which are identical to helium nuclei
(2n, 2p, +2 charge) emitted from the
nucleus
- Energy range from 3 to 8 MeV (most
are around 5); alphas from a given
isotope are all of the same energy
- Have a very short range in air (a
few cm) or tissue
- Common example are: polonium-210, uranium-238, and plutonium-239